kernel headers and glibc

Seeking enlightenment...

In the KernelHeaders.WARNING file it says:

As a general rule, installing kernel headers that are newer than the kernel glibc was compiled with *may* cause problems, so unless you need these for a particular reason it's best to stick with the 2.4.x kernel-headers package for now.

...and so I've never installed the kernel headers for the 2.6.x kernels. In the current/Changelog it says:

glibc-2.3.6-i486-6.tgz: Recompiled against 2.4.33.3 and 2.6.17.13 headers

So does that mean I can/should install the 2.6.17 kernel headers?

Thanks in advance,

Brian

That means you CAN install the 2.6.x kernel-headers but you SHOULD stick with the 2.4.x for now, unless you need them for something which explicitly requires the 2.6.x kernel-headers.

So what does he mean when he says that glibc was compiled against 2.6.17 headers? I'm just trying to get my mind around this.

Thanks,
Brian

I was under the impression that it was an 'or' situation rather than an 'and' situation. As I understand it, you could have either the 2.4 headers or the 2.6 headers that Pat compiled. I, for one, was looking forward to having a 2.4-free system and compiling glibc against both headers was the solution for that.

Everything I find on this subject is the same song I've heard but I haven't found anything that makes much sense to me as far as not being able to compile against both headers. Really... my question is whether or not it is possible to compile against both sets of headers and still get the same glibc package. Logic says it's not possible, I know... but Pat's changelog leads me to believe otherwise.

So basically... despite the changelog saying that glibc is compatible to both... 2.4 headers for glibc and 2.6 headers for kernel-du-jour as usual? I'm very confused.

I don't know how (or if) you can compile against 2 versions - but here's what running /lib/libc-2.3.6.so on my Slackware -current system outputs:

/lib/libc-2.3.6.so
GNU C Library stable release version 2.3.6, by Roland McGrath et al.
Copyright (C) 2005 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
Compiled by GNU CC version 3.4.6.
Compiled on a Linux 2.4.33.3 system on 2006-09-14.
Available extensions:
        GNU libio by Per Bothner
        crypt add-on version 2.1 by Michael Glad and others
        GNU Libidn by Simon Josefsson
        linuxthreads-0.10 by Xavier Leroy
        BIND-8.2.3-T5B
        libthread_db work sponsored by Alpha Processor Inc
        NIS(YP)/NIS+ NSS modules 0.19 by Thorsten Kukuk
Thread-local storage support included.
For bug reporting instructions, please see:
<http://www.gnu.org/software/libc/bugs.html>.

Here's how you get it:

mingdao@test:~$ /lib/libc-2.3.6.so
GNU C Library stable release version 2.3.6, by Roland McGrath et al.
Copyright (C) 2005 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
Compiled by GNU CC version 3.4.6.
Compiled on a Linux 2.4.33.3 system on 2006-09-14.
Available extensions:
        GNU libio by Per Bothner
        crypt add-on version 2.1 by Michael Glad and others
        GNU Libidn by Simon Josefsson
        linuxthreads-0.10 by Xavier Leroy
        BIND-8.2.3-T5B
        libthread_db work sponsored by Alpha Processor Inc
        NIS(YP)/NIS+ NSS modules 0.19 by Thorsten Kukuk
Thread-local storage support included.
For bug reporting instructions, please see:
<http://www.gnu.org/software/libc/bugs.html>.

mingdao@test:~$ /lib/tls/libc-2.3.6.so
GNU C Library stable release version 2.3.6, by Roland McGrath et al.
Copyright (C) 2005 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
Compiled by GNU CC version 3.4.6.
Compiled on a Linux 2.6.17.13 system on 2006-09-14.
Available extensions:
        GNU libio by Per Bothner
        crypt add-on version 2.1 by Michael Glad and others
        GNU Libidn by Simon Josefsson
        Native POSIX Threads Library by Ulrich Drepper et al
        BIND-8.2.3-T5B
        NIS(YP)/NIS+ NSS modules 0.19 by Thorsten Kukuk
Thread-local storage support included.
For bug reporting instructions, please see:
<http://www.gnu.org/software/libc/bugs.html>.

I must admit to more ignorance than understanding here. But someone
such as Alien Bob will come along and add clarity -- bank on it.

I wanted an entire Slackware-11.0 RC4 2.6.17.13 system. This one was
installed with huge26.s, than afterwards these were added:

mingdao@test:~$ ls -l /var/log/packages/kernel-*2.6.17.13*
-rw-r--r-- 1 root root     963 2006-09-16 08:02 /var/log/packages/kernel-generic-2.6.17.13-i486-1
-rw-r--r-- 1 root root   43671 2006-09-17 03:51 /var/log/packages/kernel-headers-2.6.17.13-i386-1
-rw-r--r-- 1 root root  103482 2006-09-16 08:00 /var/log/packages/kernel-modules-2.6.17.13-i486-1
-rw-r--r-- 1 root root 1328332 2006-09-16 08:01 /var/log/packages/kernel-source-2.6.17.13-noarch-1

When you install with huge26.s, the first boot says the kernel is
2.6.17.13. But the only thing in the system relating to 2.6.17.13
at that point is /boot/vmlinuz, which is NOT a symlink. It is only
the kernel image from ../slackware-current/kernels/huge26.s/bzImage.

You must reboot and install everything else or you still have ONLY
the 2.4.33.3 modules, headers, source, and config file.

Originally posted by BCarey

So what does he mean when he says that glibc was compiled against 2.6.17 headers?

Read Pat's comments in these files, as well as the -current ChangeLog:

./slackware-current/README.NPTL
./slackware-current/RELEASE_NOTES

If you'll notice from my post above, glibc is installed in two separate
$PATHs. One uses the 2.4.33.3 headers; the other uses 2.6.17.13 headers.

Maybe you don't need the 2.6 headers as nykey stated; but if you do,
they are available.

I ran rt2500.SlackBuild and built okay.

At the risk of sounding thick-headed:

Reading those files tells me that, at the very least, the 2.4 headers should be installed and the 2.6 headers are a good idea if using any sort of 2.6 kernel.

Am I remotely close?

basically, you wanna stick with the 2.4 headers (even if you're running kernel 2.6) unless you have some specific need for the 2.6 ones... and if you use the 2.6 ones, make sure you use the version glibc was compiled with, not a newer kernel-of-the-day version...

Got it... that's what I figured.

What I was trying to ask in my last post was 2.4 headers are a given and 2.6 headers were an option when using a 2.6 kernel. My question has been answered, though.

Thanks.